Salmon Cleaner Fish Welfare in Aquaculture

Cleaner fish including wrasse and lumpfish are used in salmon farming to control sea lice, but their own welfare needs are frequently neglected in commercial aquaculture systems.

Key Facts

Approximately 60 million wrasse and lumpfish are used annually in Norwegian salmon farming for biological lice control
Cleaner fish are often sourced from wild capture fisheries that raise additional welfare and sustainability concerns
Many cleaner fish die before completing their lice control function, with mortality rates of 50-80% common
Wrasse have complex behavioural needs including social structure, shelter use, and species-specific activity patterns
Lumpfish show individual personality traits and learning capabilities in research settings
Welfare standards specific to cleaner fish are largely absent from salmon aquaculture certification schemes

Welfare Considerations

Cleaner fish welfare represents a significant and largely invisible welfare issue within salmon aquaculture. These small fish, used as a biological tool for sea lice control, are often treated as disposable equipment rather than as sentient animals with their own welfare needs. High mortality rates indicate that their fundamental welfare needs — species-appropriate social structures, shelter, appropriate temperature, and sufficient food alongside their lice-cleaning role — are frequently unmet. Wrasse in particular have complex social behaviour that is difficult to accommodate in salmon net pen environments. The scale of cleaner fish use — tens of millions annually — makes this a numerically significant welfare issue even if individual fish are assigned lower moral weight than salmon.

What You Can Do

Support certification schemes that extend welfare requirements to cover cleaner fish species
Advocate for welfare standards for cleaner fish to be developed and required in salmon aquaculture licensing
Choose salmon from producers using mechanical lice removal or other non-animal methods over cleaner fish where available
Support research into cleaner fish welfare needs and improved husbandry practices
Engage with aquaculture certification bodies about including cleaner fish welfare in their standards
Reduce salmon consumption from systems that rely heavily on cleaner fish without demonstrated welfare standards